Discussion of Question with ID = 052 under Problems-on-Trains

This is the discussion forum for this question. If you find any mistakes in the solution, or if you have a better solution, then this is the right place to discuss. A healthy discussion helps all of us, so you are requested to be polite and soft, even if you disagree with the views of others. The question and its current solution has also been given on this page.



Two trains are moving in same direction on two parallel tracks. How many seconds will they take to cross each other if the sum of their lengths is 332m, and the difference of their speeds is 83m/s?


4 sec.


5 sec.


3 sec.


6 sec.

Ans: a

The total distance is equal to the sum of the lengths of the trains, so s = 332. This distance has to be covered at a net relative speed equal to the difference of the speeds of the two trains, so v = 83. The time will be distance/speed = $332/83$ = 4s.

Comments and Discussion